Method of imparting crease resistance to cellulosic fibers by treating them with tetraoxymethylene

ABSTRACT

This invention is to provide a method of imparting crease resistance and soft touch to cellulosic fibers or textile fabrics and knitted goods containing cellulosic fibers by treating them with tetraoxymethylene in the presence of a certain catalytic mixture.

United States Patent [191 Yanai Dec. 17, 1974 [73] Assignee: NisshinBoseki Kabushiki Kaisha,

Tokyo, Japan [22] Filed: Aug. 10, 1972 [21] App]. No.: 279,362

[52] US. Cl. 8/116.4, 8/116 R [51] Int. Cl. D06m 13/12, D06m 13/14 [58]Field of Search 8/116 R, 116.4

[56] References Cited UNITED STATES PATENTS l/1965 Husebeck et a1.8/116.4 3/1965 Daul et a1. 8/116.4

7/1972 Miyake et a1. 8/116.4 7/1972 Asahi et al....., 8/1 16.4

OTHER PUBLICATIONS Pierce et 211., American Dyestuff Reporter, May,1970, p. 50.

Reid et a1., Textile Chemist and Colorist, 3, (8), 51-53, (1971).

Primary ExaminerGe0rge F. Lesmes Assistant ExaminerJ. Cannon Attorney,Agent, or FirmRobert E. Burns; Emmanuel J. Lobato; Bruce L. Adams [57]ABSTRACT This invention is to provide a method of imparting creaseresistance and soft touch to cellulosic fibers or textile fabrics andknitted goods containing cellulosic fibers by treating them withtetraoxymethyiene in the presence of a certain catalytic mixture.

4 Claims, N0 Drawings METHOD OF IMPARTING CREASE RESISTANCE TOCELLULOSIC FIBERS BY TREATING THEM WITH TETRAOXYMETHYLENE DETAILEDEXPLANATION OF THE INVENTION This invention relates to a method ofimparting crease resistance and soft touch to cellulosic fibers ortextile fabrics and knitted goods containing cellulosic fibers bytreating them with tetraoxymethylene in the presence of a catalyticmixture of a certain metalboron fluoride and a certain organiccarboxylic acid.

It is known that tetraoxymethylene is a cyclic tetramer of formaldehyde(CH O) and that it is a needle- ]ike crystal which has the melting pointof 112C and is difficult in liberating free formaldehyde in comparisonwith other derivatives of formaldehyde. Tetraoxymethylene has beenreported by Staudinger and et al. in Helv. Chim. Acta 848, 65 publishedin the year 1925 but it has not yet been used in the industrial fielduntil today because an industrial and economical method for theproduction of tetraoxymethylene has not been developed.

Now, some industrial and economical methods for the production oftetraoxymethylene are proposed and they are explained in Japanese PatentPublication Nos. 5352/69, 2222/69, l675l/68 and 28460/68, and as aresult, the industrial way for utilizing tetraoxymethylene has beenopened.

Also, Japanese Patent Publication Nos. 21356/65, 8877/66, 953/67 and23635/68 disclose methods for utilizing tetraoxymethylene and it isnoted that they relate to the use of tetraoxymethylene as a raw materialfor the production of high molecular materials but they do not relate tothe use of tetraoxymethylene for treating cellulosic fibers. Further,U.S. Pat. No. 3,186,945 discloses the use of a catalyst comprising anorganic acid such as citric acid and a metal salt of Lewis type acid forthermally treating free aldehydes or some compounds capable ofliberating free aldehydes or thermally reactive aldehyde resins. It isnoted in claims and Examples of the U.S. Patent that formaldehyde ormethylol triazone is used in the presence of a catalyst comprisingcitric acid and hexahydrated magnesium nitrate in the weight ratio of2:7, which is referred as to a 2-7 catalyst or a catalyst comprisingcitric acid, strontium nitrate and hexahydrated magnesium nitrate in theweight ratios of 2:314, which is referred as to a 2-3-4 catalyst or acatalyst comprising citric acid and hexahydrated magnesium nitrate inthe weight ratio of 5:12, which is referred as to a 5-12 catalyst, butit is noted that the U.S. Patent does not disclose the use oftetraoxymethylene and a catalytic mixture of a metalboron fluoride andan organic carboxylic acid used in accordance with this invention. Itwas found that the 2-7 catalyst, 2-3-4 catalyst and 5l2 catalyst varygreatly in their effects depending on the temperature and are lesseffective as the catalysts for tetraoxymethylene and so they can not beused practically when cellulosic fibers or textile fabrics and knittedgoods containing the cellulosic fibers are treated withtetraoxymethylene.

Still further, the American Dyestuff Reporter, Vol. 57 1968), page 864discloses the use of an active catalyst comprising a metal halide and ahydroxy or an alkoxy substituted carboxylic acid but it is noted thatthe active catalyst is different from the catalytic mixture ofmetal-boron fluoride and an organic carboxylic acid used in accordancewith this invention. Also it was found that such an active catalyst cannot be used as a catalyst for tetraoxymethylene.

The inventor has investigated various methods for a long time in whichtetraoxymethylene is used for imparting crease resistance to cellulosicfibers or textile fabrics and knitted goods containing cellulosic fibersand as a result, the inventor has discovered this invention in whichtetraoxymethylene can be practically used in the presence of a catalyticmixture of at least one of metal-boron fluorides and at least one oforganic carboxylic acids as listed below.

Namely, some examples of the metal-boron fluorides are magnesium-boronfluoride, aluminum-boron fluoride, zinc-boron fluoride, cadmium-boronfluoride, tinboron fluoride and lead-boron fluoride. Also some examplesof the organic carboxylic acids are formic acid, oxalic acid, malonicacid, succinic acid, maleic acid, maleic acid anhydride, glycollic acid,lactic acid, malic acid, citric acid and tartaric acid. It is preferableto use the water soluble metal-boron fluorides and organic carboxylicacid.

The advantageous merits achieved in accordance with this invention byusing tetraoxymethylene for imparting crease resistance to cellulosicfibers or textile fabrics and knitted goods containing cellulosic fibersare summarized as follows.

1. An excellent soft touch is imparted to the finished products contraryto the amino-plastic resins which impart rough touch to the finishedproducts. It is considered that such a merit is achieved on the basis ofthe facts that tetraoxymethylene can easily be penetrated into thecellulosic fibers and also that the self-polymerization oftetraoxymethylene and the formation of the resinous products areprevented on the surfaces of the cellulosic fibers as tetraoxymethyleneis Sublimated at elevated temperatures.

2. Tetraoxymethylene is the tetramer of formaldehyde not containing anitrogen atom or atoms contrary to the resinous substances, which areused as the usual anti-creasing agents, containing a nitrogen atom oratoms and therefore the cellulosic fibers or the textile fabrics andknitted goods containing the cellulosic fibers are not degraded in theirquality due to the absorption of chlorine but they are improved in theirlightresistance and thermal resistance.

3. The chemicals required for treating textile fabrics and knitted goodsare reduced in amount to about 30% of the glyoxal-monourea type resinsin order to impart the same degree of crease resistance to such textilefabncs.

4. Formaldehyde is retained in a very small amount or not retained inthe finished textile fabrics and knitted goods and so they can be usedfreely due to absence of bad effects on the health.

Now, in the art there is an important problem in that mechanicalstrength of the finished textile fabrics is remarkably reduced whentetraoxymethylene is used in the presence of the known catalysts whichare used in combination with the usual anti-creasing agents andtherefore, in such a case, it is necessary to control exactly theconditions for treating the textile fabrics in order to keep theirmechanical strength at the degree required for the practical use andsimultaneously to achieve the crease resistance required for practicaluse.

As it is obvious from the description indicated hereinafter, the creaseresistance and mechanical strength of the finished textile fabrics aredistinguishably varied depending on the heating temperature when theknown catalysts are used and therefore it is impossible to control theconditions for treating the textile fabrics for producing the finishedstable and crease-resistance products. Also, the known catalysts have aweak catalytic effect on tetraoxymethylene and therefore it is necessaryto use tetraoxymethylene at elevated temperatures in order to impartsatisfactory crease resistance to cellulosic fibers or the textilefabrics and knitted goods containing the cellulose fibers; it was foundin such a case that the textile fabrics become brittle and are yellowcolored and so the finished products are of no practical use.

On the contrary, the catalytic mixture used in this invention can beused in the wide ranges of heating temperatures used to impart thecrease resistance to the textile fabrics, and the resultant textilefabrics have neither decreased mechanical strength nor were they yellowcolored. Therefore, the catalytic mixture of this invention is the mostimportant to achieve crease resistance of the cellulosic fibers whenthey are treated with tetraoxymethylene and it can be said that it is anew discovery by the inventor to use tetraoxymethylene for impartingcrease resistance to cellulosic fibers.

lt is preferable to use the metal-boron fluorides in an amount of 0.02to 10.0% by weight of the textile fabrics and knitted goods containingthe cellulosic fibers and also it is preferable to use the organiccarboxylic acids in an amount of 0.02 to 10.0% by weight of the textilefabrics and knitted goods. lt is noted that the cellulosic fibers andtextile fabrics can be treated for a short period of time at a lowertemperature as the amount of the catalytic mixture increases. In such acase, the cellulosic fibers tend to decompose and therefore theconcentration of the catalytic mixture used in this invention must beadjusted depending on the conditions of the heat treatment for thecellulosic fibers.

Tetraoxymethylene can be used in an amount of 0.1 to 10.0% by weight ofthe cellulosic fibers or the textile fabrics and knitted goods and it ispreferable to use tetraoxymethylene in an amount of 0.3 to 4.0% byweight of the cellulosic fibers or the textile fabrics.

Tetraoxymethylene can be applied onto the cellulosic fibers or thetextile fabrics by dipping them into sprayed cellulosic fibers ortextile fabrics in the same The cellulosic fibers or the textile fabricsand knitted goods containing the cellulosic fibers thus treated withtetraoxymethylene and the catalytic mixture of this invention are driedand then subjected to a heat treatment. It is necessary to take care inhandling the dried materials because tetraoxymethylene is Sublimatedwhen the dried materials are left for some time as they are.

The heat treatment can be carried out at a temperature of 100C to 220Cand it is preferable to carry out the heat treatment at a temperature of120C to 180C for 1 to 3 minutes. It is noted that the time required forthe heat treatment can be shortened as the heating temperatureincreases. Also it is noted that the heat treatment can be conducted byusing a hot air, a heated oil,

a molten metal bath, a heated roll, a hot press and other devices.

It is obvious to those skilled in the art that tetraoxymethylene and thecatalytic mixture used in accordance with this invention can be used incombination with various kinds of assistants such as softeners,finishing agents, soil-release agents, water-proofing agents, antistaticagents and flame-proofing agents for imparting a desirable quality tothe finished textile fabrics and knitted goods.

This invention is illustrated by the following Examples.

EXAMPLE 1 Each of eight test samples of scoured, bleached and mercerizedcotton cloth, which is woven of the warps of 40 yarn counts and thewefts of 30 yearn counts, and has the weight of 125 grams/square meter,was dipped into each of aqueous solutions 1 to 8 which are prepared bymixing water (as a solvent) and the chemical agents as indicated in thefollowing Table l in the indicated grams per 100 cc of the aqueoussolution.

Table 1 Chemical Agents Nos. of Agueous Solgtions Zinc-boron fluorideHexahydrated zinc nitrate Hexahydrated magnesium chloride Hexahydratedmagnesium nitrate Anhydrous strontium nitrate Monohydrated citric acidTetraoxymethylene Polyethylene softener N ote:

( l Aqueous solution No. l was prepared by using the catalytic mixtureof this invention.

(2) Aqueous soiution No. 5 was prepared by using the 2-7 catalystdisclosed in the US. Pat. 3.186.954.

(3) Aqueous solution No. 6 was prepared by using the 2-3-4 catalystdisclosed in the US. Pat. 3.l86.954.

(4) Aqueous solution No. 7 was prepared by using the 5-12 catalystdisclosed in the U.S. Put. 3.186.954.

(5) Aqueous solution No. 8 was prepared by using the active catalystdisclosed in the American Dyestull" Reporter. Vol. 57 was 1.

page 864.

a tetraoxymethylene-containing solution or by spraying thetetraoxymethylene-containing solution on to them and then by squeezingor dehydrating the dipped or Then the dipped test samples were mangledto a wet pick-up of about and dried in a non-touched drier at 125C forseconds and then the dried test samples were heat-treated in a pilotbaking machine at 130C for 2 minutes or 140C for 2 minutes or 160C for 2minutes and then the heat-treated test samples were washed with aneutral soap solution and dried in a tumbler type drier. The dried testsamples were tested for the degree of crease resistance by using thetest method disclosed in AATCC, 661968 and also they were tested fortear strength by using the pendulum method disclosed in the JapaneseIndustrial Standards L useful for treating the cotton cloth withtetraoxymethylene but also that other catalysts are not suitable.

EXAMPLE 2 Eight test samples were prepared by using a cloth which iswoven of a mixed yarn having the 40 counts and consisting of polyesterfibers (65%) and cotton fibers (45%). The test samples were scoured,bleached,

1004-1959. The test results are given in the following mercerized andheat-set. Each of the test samples was Table 2. dipped into each of theaqueous solutions 1 to 8 dis- Table 2 Nos. of Test Nos. of AqueousHeat-treated Crease Recovery Tear Strength(g) samples solutions at (C)Angle (dry) in the direction of the warp As it is obvious from the Table2, the test sample 1 is not changed in its crease resistance and tearstrength even if it is heat-treated at 130C or 140C or 160C but the testsamples 2 to 8 are widely changed in their crease resistance and tearstrength after they are heattreated at the difi'erent heatingtemperature. This proves that the catalytic mixture of this invention isclosed in Example 1 and then they were heat-treated in the same manneras in Example 1. The resultant test samples were tested for their washand wear rating by using the l-B method disclosed in AATCC, 124-1967 andalso they were tested for tear strength in the same manner as inExample 1. The test results are given in the following Table 3.

Table 3 Nos. of Test Nos. of Aqueous Heat-treated Wash and TearStrength(g) samples solutions at (C) Wear Rating in the direction(Grade) of the weft As it is obvious from the Table 3, the test sample 1are practically useful for treating the textile fabric conhas the goodand stable wash and wear rating but other wining u osic fibers. samples2 to 8 are changed in their wash and wear rating depending on thevariation of heating temperature. EXAMPLE 4 This proves that thecatalytic mixture of this invention Exampe i was repeated with theexception that is practically useful but the other known catalysts areaqueous Solutions 18 to 22 were used The aqueous not suitable fortreating the textile fabric containing hmons 18 to 22 were prepared bymixing water 3 9911111051: fibem solvent) and the chemical agents asindicated in the fol- EXAMPLE 3 lowing Table 5 in the indicated gramsper 100 cc of the Example 1 was repeated with the exception that aqueoussolution.

Table Nos. of Aqueous Solutions Chemical Agents 18 19 2O 21 Magnesiumboron fluoride(40%) 1.4

Aluminum-boron fluoride(30%) 1.4

Cadmium-boron fluoride(50%) 3.0

Tin-boron fluoride(47%) 1.4

Lead-boron fluoride(50%) 2.5

Monohydrated citric acid 0.5 0.5 0.5 0.5 0.5

Tetraoxymethylene 3.0 3.0 3.0 3.0 3.0

Polyethylene(softener) 2.0 2.0 2.0 2.0 2.0

aqueous solutions 9 to 17 were used. The aqueous solu- The resultanttest samples 18 to 22 were tested their tions 9 to 17 were prepared bymixing 3.0 grams/100 crease resistance and tear strength in the samemanner cc of tetraoxymethylene, 2.0 grams/ 100 cc of polyethas inExample 1. The test results are given in the followylene softener and1.5 grams of a 45% solution of zincing Table 6. As it is obvious fromthe Table 6, the test boron fluoride/100 cc with 0.5 gram/100 cc of anor- 3 samples 18 to 22 have the good and stable crease resisganiccarboxylic acid selected from the group consisttance and tear strength.Also it was found that all the Table 6 Nos. of Nos. of Crease RecoveryAngle(dry) Tear Strength(g) in Test Samples A ueous J th dire tion f thw- So utions 0 ing of (9) formic acid, (10) dihydrated oxalic acid, testsamples are soft touch and improved in their ther- (ll) malonic acid,(12) succinic acid, (13) maleic mal resistance, light-resistance andchlorine-resistance. acid, (14) glycollic acid, (15) lactic acid, (16)malic acid and (17) tartaric acid. The resultant test samples EXAMPLE 59 to 17 were tested for theiir crease resistance and tear Example 1 wasrepeated with the exception that Strength in the same manner as inExample The test aqueous solutions 23 to 28 were used. The aqueoussoresults are given in the following Table 4. As it is ObVllungns 23 to28 were prepared by mlxmg water (as a 01-18 from the Table 4, 1116 testSamples 9 l0 17 have the solvent) and the chemical agents as indicatedin the folgood and stable crease resistance and tear strength. lowingTable 7 in the indicated grams per cc of the This proves that thecatalytic mixtures of this invention aqueous solution.

Table 4 Crease Recovery Ang1e(dry) Tear Strength (g) Nos. of Test Nos.of Aqueous tn the direction Samples Solutions of th Table 7 Nos. of Aueous Solutions Chemical Agents 23 24 23 27 28 Magnesium-boron fluoride(40%) 0.7 0.7 Aluminium-boron fluoride Zinc-boron fluoride Tin-boronfluoride 0.7 0.7 Dih drated oxalic acid 0.2 0.1

eic acid 0.2 0.2 Monohydrated citric acid 0.5 0.5 0.2 0.2 Tartaric acid0.2 0.2 Tetraoxymethylene 3.0 3.0 3.0 3.0 3.0 3.0 Polyethylene(softener) 2.0 2.0 2.0 2.0 2.0 2.0

The resultant test samples 23 to 28 were tested their 3. The method forimparting crease resistance and crease resistance and tear strength inthe same manner soft touch to material selected from cellulosic fibersas in Example l. The test results are given in the followand textilefabrics and knitted goods containing the celing Table 8. As it isobvious from the Table 8, the test lulosic fibers as claimed in claim 1,wherein the treat- 20 samples 23 120 28 have the good and stable CI'BBSCI6S1S- ment 15 conducted at a temperature of about 130C, for tance andtear strength even if the heat treatments are 1 t 3 i te conducted atthe different temperature 4. The method for imparting crease resistanceand Table 8 Nos. of Tear Strength in Nos. of Test Aqueous CreaseRecovery Angle(dry) the direction 0 the samples solutions w treated I30C 140C 160C 130C 140 160C What I claim is that: soft touch to materialselected from cellulosic fibers 1. A method for imparting creaseresistance and soft and textile fabrics and knitted goods containing theceltouch to a material selected from cellulosic fibers, and lulosicfibers as claimed in claim 1, wherein said metaltextile fabrics andknittd goods containing cellulosic boron fluoride is selected from amember of the group fibers comprising treating said material at atemperaconsisting of magnesium-boron fluoride, aluminumture of about120C to 130C with 0.1 to 10% tetraoxoron flu id zin n fl d r nymethylene in the presence of a catalytic mixture of fluoride, tin-boronfluoride and lead-boron fluoride, 0.02 to 10% ofa metal-boron fluorideand 0.02 to 10% and said organic carboxylic acid is selected from a ofan organic carboxylic acid, said percentages being member of the groupconsisting of formic acid, oxalic by weight of s id materi l, acid,malonic acid, succinic acid, maleic acid, maleic 2. The method forimparting crease resistance and acid nhy g y acid. lactic a malic a softtouch to material selected from cellulose fibers, Citric mild andtartaric 301d.

textile fabrics and knitted goods containing the cellulosic fibers asclaimed in claim 1, wherein the treatment is conducted at a temperatureof about 130C.

1. A METHOD FOR IMPARTING CREASE RESISTANCE AND SOFT TOUCH TO A MATERIALSELECTED FROM CELLULOSIC FIBERS, AND TEXTILE FABRICS AND KNITTED GOODSCONTAINING CELLULOSIC FIBERS COMPRISING TREATING SAID MATERIAL AT ATEMPERATURE OF ABOUT 120*C TO 130*C WITH 0.1 TO 10% TETRAOXYMETHYLENE INTHE PRESENCE OF A CATALYTIC MIXTURE OF 0.02 TO 10% OF A METAL-BORONFLUORIDE AND 0.02 TO 10% OF AN ORGANIC CARBOXYLIC ACID, SAID PERCENTAGESBEING BY WEIGHT OF SAID MATERIAL.
 2. The method for imparting creaseresistance and soft touch to material selected from cellulose fibers,textile fabrics and knitted goods containing the cellulosic fibers asclaimed in claim 1, wherein the treatment is conducted at a temperatureof about 130*C.
 3. The method for imparting crease resistance and softtouch to material selected from cellulosic fibers and textile fabricsand knitted goods containing the cellulosic fibers as claimed in claim1, wherein the treatment is conducted at a temperature of about 130*C.for 1 to 3 minutes.
 4. The method for imparting crease resistance andsoft touch to material selected from cellulosic fibers and textilefabrics and knitted goods containing the cellulosic fibers as claimed inclaim 1, wherein said metal-boron fluoride is selected from a member ofthe group consisting of magnesium-boron fluoride, aluminum-boronfluoride, zinc-boron fluoride, cadmium-boron fluoride, tin-boronfluoride and lead-boron fluoride, and said organic carboxylic acid isselected from a member of the group consisting of formic acid, oxalicacid, malonic acid, succinic acid, maleic acid, maleic acid anhydride,glycolic acid, lactic acid, malic acid, citric acid and tartaric acid.